Flexible hose construction and method of making the same

ABSTRACT

A flexible hose construction and method of making the same are provided, the flexible hose construction comprising an inner corrugated hose made of polymeric material and having a plurality of outwardly convex projections with recesses therebetween and extending from one end thereof to the other end thereof, an outer sleeve of reinforcing material disposed in telescoping relation on the inner hose, and a tube of polymeric material disposed between the sleeve of reinforcing material and the inner hose and extending in a generally straight-line manner from projection to projection of the inner hose so as to tend to prevent the sleeve of reinforcing material from entering into the recesses of the inner hose an amount that would end to substantially reduce the flexibility characteristics of the inner hose.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a new flexible hose construction and to a newmethod of making such a flexible hose construction.

2. Prior Art Statement

It is known to provide a flexible hose construction comprising an innercorrugated hose made of polymeric material and having a plurality ofoutwardly convex projections with recesses therebetween and extendingfrom one end thereof to the other end thereof, and an outer sleeve ofreinforcing material disposed in telescoping relation on the inner hose.For example, see the U.S. Pat. No. to Medford et al, 4,415,389.

SUMMARY OF THE INVENTION

It is one feature of this invention to provide a new flexible hoseconstruction wherein the flexibility characteristics of an innercorrugated hose thereof are not substantially diminished by having anouter sleeve of reinforcing material extend into the recesses defined bythe corrugations of the inner hose an amount that would diminish suchflexibility characteristics.

In particular, it was found according to the teachings of this inventionthat a tube of polymeric material can be disposed between the sleeve ofreinforcing material and the inner hose and extend in a generallystraight-line manner from projection to projection of the inner hose soas to tend to prevent the sleeve of reinforcing material from enteringinto the recesses of the inner hose an amount that would tend tosubstantially reduce the flexibility characteristics of the corrugatedinner hose.

In this manner, it was found according to the teachings of thisinvention, that the inner corrugated hose could be formed of athermoplastic material that readily permits the flexible hoseconstruction to be utilized for conveying a volatile liquidtherethrough, such as gasoline for transportation vehicles and the like,and still permit the hose construction to be sufficiently flexible andlightweight so that the same can be readily bent into the desired shapethereof for its intended conveying purpose.

For example, one embodiment of this invention provides a flexible hoseconstruction comprising an inner corrugated hose made of polymericmaterial and having a plurality of outwardly convex projections withrecesses therebetween and extending from one end thereof to the otherend thereof, an outer sleeve of reinforcing material disposed intelescoping relation on the inner hose, and a tube of polymeric materialdisposed between the sleeve of reinforcing material and the inner hoseand extending in a generally straight-line manner from projection toprojection of the inner hose so as to tend to prevent the sleeve ofreinforcing material from entering into the recesses of the inner hosean amount that would tend to substantially reduce the flexibilitycharacteristics of the inner hose.

Accordingly, it is an object of this invention to provide a new flexiblehose construction having one or more of the novel features of thisinvention as set forth above or hereinafter shown or described.

Another object of this invention is to provide a new method of makingsuch a flexible hose construction, the method of this invention havingone or more of the novel features of this invention as set forth aboveor hereinafter shown or described.

Other objects, uses and advantages of this invention are apparent from areading of this description which proceeds with reference to theaccompanying drawings forming a part thereof and wherein:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a fragmentary perspective view, partially in cross section,and illustrating the new flexible hose construction of this invention.

FIG. 2 is an enlarged fragmentary side view, partially in cross section,and illustrating the inner corrugated hose of the hose construction ofFIG. 1.

FIG. 3 is a view similar to FIG. 2 and illustrates the inner corrugatedhose of FIG. 2 having a unique tube of polymeric material disposedthereon according to the method of this invention.

FIG. 4 is a view similar to FIG. 3 and illustrates how a sleeve ofreinforcing material is disposed on top of the tube of polymericmaterial that has been placed on the inner corrugated hose asillustrated in FIG. 3.

FIG. 5 is a view similar to FIG. 4 and illustrates how an outerpolymeric layer is disposed over the reinforcing sleeve of FIG. 4 tocomplete the hose construction of this invention that is illustrated inFIG. 1.

FIG. 6 is a fragmentary view similar to FIG. 2 and illustrates anotherembodiment of the inner corrugated hose.

FIG. 7 is a fragmentary perspective view similar to FIG. 1 andillustrates how a tube of polymeric material and a reinforcing sleevecan be disposed in series on the corrugated hose of FIG. 6.

FIG. 8 is a view similar to FIG. 7 and illustrates a completed hoseconstruction of this invention made from the structure of FIG. 7 byhaving an outer polymeric layer disposed over the reinforcing layer ofthe structure of FIG. 7.

FIG. 9 is an enlarged fragmentary cross-sectional view of another innerhose of this invention for the hose constructions of this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

While the various features of this invention are hereinafter illustratedand described as being particularly adapted to provide a flexible hoseconstruction for conveying gasoline and like volatile liquidstherethrough, it is to be understood that the various features of thisinvention can be utilized singly or in various combinations thereof toprovide a flexible hose construction for conveying any other fluidtherethrough for other types of apparatus as desired.

Therefore this invention is not to be limited to only the embodimentsillustrated in the drawings, because the drawings are merely utilized toillustrate one of the wide variety of uses of this invention.

Referring now to FIG. 1, the new flexible hose construction of thisinvention is generally indicated by the reference numeral 20 andcomprises an inner corrugated hose 21 formed of any suitable polymericmaterial and having a plurality of outwardly convex projections 22 withrecesses 23 therebetween and extending from one end 24 to the other end25 thereof, a tube 26 of any suitable polymeric material extending in agenerally straight-line manner from projection 22 to projection 22 asillustrated in FIG. 3, an outer sleeve 27 of any suitable reinforcingmaterial disposed in telescopic relation on the tube 26, and an outerlayer 28 of any suitable polymeric material that will provide aprotection for the sleeve 27 of reinforcing material and also to tend toprevent any liquid that is conveyed through the flexible hoseconstruction 20 from permeating to the exterior thereof, such asgasoline and the like.

As previously stated, it was found according to the teachings of thisinvention that the hose construction 20 can be relatively flexiblebecause of the corrugated inner hose 21 thereof.

However, it was further found according to the teachings of thisinvention that the flexibility characteristics of such a hoseconstruction 20 is diminished if a sufficient amount of the reinforcingmeans 27 is received in the recesses 23 of the inner hose 21 to resistthe bending thereof.

Therefore, it was further found according to the teachings of thisinvention that by providing the tube 26 of polymeric material on theinner hose 21 before disposing the reinforcing sleeve 27 thereon withthe tube 26 being so constructed and arranged that the same extendssubstantially from the apex 29 of one projection 22 to the next apex 29of the next adjacent projection 22 in a substantially straight-linemanner illustrated in FIG. 3, the tube 26 will substantially resist thepenetration of the reinforcing layer 27 into the recesses 23 of theinner hose 21 to any great degree even though the reinforcing layer 27is being forced radially inwardly either through the normal effect ofapplying the same onto the inner hose 21 and/or by the force of theouter cover 28 being applied over the reinforcing means 27 in aconventional hose forming manner, such slight penetration of thereinforcing means 27 being illustrated in FIGS. 4 and 5, whereby it canbe seen that the recesses 23 remain substantially void of thereinforcing means 27 so as to retain the desired flexibilitycharacteristics of the inner hose 21.

While the inner hose 21 of the hose construction 20 of this inventioncan be formed of any suitable material and in any suitable manner, oneworking embodiment thereof comprises thermoplastic material that is blowmolded in a conventional manner into the configuration illustrated inFIG. 2 wherein the convolutions or projections 22 thereof are annularand are uniformly spaced from each other throughout the length of thehose 21 or can be disposed in a helical manner throughout the length ofthe hose as represented by the projections 22A illustrated in FIG. 6wherein another inner hose of this invention is indicated by thereference numeral 21A and parts thereof similar to the inner hose 21previously described are indicated by like reference numerals followedby the reference letter "A". The inner hose 21A is made in aconventional manner by spirally wrapping a strip 30 that has theprojections 22A and recesses 23A formed therein in any suitable mannerand forming a helically disposed seam 31 throughout the length of theinner hose 21A.

One problem with thermoplastic hoses currently being made is thestiffness thereof when compared to elastomeric rubber hoses of the sameinner and outer dimensions. The stiffness of the prior knownthermoplastic hoses is due to the rigidity of the plastic material.However, by using a convoluted or corrugated inner tube, the flexibilityof the thermoplastic hose can be made greater than a rubber hose of thesame size. The convolutions can be annular in nature and their geometrycan be dependent upon the size of the hose to be produced.

A thermoplastic hose with a corrugated inner tube also has otheradvantages over conventional rubber hoses.

In particular, a plastic hose construction built with a convoluted innercorrugated hose has better kink resistance and a smaller bend radiusthan a rubber hose of the same size.

These properties are a result of the annular rings that form theconvoluted tube. These annular rings provide hoop strength that resultsin superior kink resistance and smaller bend radius compared to smoothinner tube hoses.

Also, a corrugated inner hose of plastic material is lighter in weightper foot than a rubber hose. To reduce kinking and bend radius,conventional rubber hoses rely on thick hose walls and/or a helix wire.In contrast, the corrugated plastic hose 21 of this invention providesan excellent kink resistance so that a lightweight, thin wall hoseconstruction 20 can be built without compromising kink resistance orbend radius.

The long-term resistance of plastic materials to degradation and wear isgreater than that of rubber materials. For example, a large number ofplastic materials are available with much better resistance tohydrocarbon-based liquids, such as gasoline, than standard rubbercompounds. Certain thermoplastics offer greater ozone, abrasion and UVresistance than rubber compounds. Thermoplastics are also more easilycolored and are more colorfast.

Therefore, the thermoplastic material of the inner hose 21 of thisinvention is chosen based on the chemical and thermal resistancerequirements of the application of the hose construction 20 and based ona means to bond the corrugated inner hose 21 to the subsequentlydisposed layers thereon.

Thus, the inner hose 21 can comprise a single layer of a homogeneousthermoplastic material as illustrated in FIGS. 2-6 or the same cancomprise an inner layer 21' of one type of thermoplastic material and anouter layer 21" of another type of thermoplastic material as providedfor the inner hose 21B illustrated in FIG. 9 as it is well known thattwo plastic materials can be extruded together to form a tubular memberhaving one material forming the outer surface thereof and the othermaterial forming the inner surface thereof and thereafter such tubularmember can be blow molded to form the same into a corrugated tubularmember.

In any event, the tube 26 of polymeric material can be applied over theinner hose 21 either as a continuous tube by conventional extrudingapparatus whereby the exuding tube 26 bonds by the nature thereof to theapexes 29 of the projections 22 in the substantially straight-linemanner illustrated in FIG. 3 or the tube 26 could be disposed in aspiral manner as illustrated in FIG. 7 and comprise a strip 32 ofpolymeric material that is helically wound onto the inner tube 21A asillustrated in FIG. 7. However, it is to be understood that the innertube 21A illustrated in FIG. 7 could be the inner tube 21 of FIG. 2 orthe inner tube 21B of FIG. 9 rather than a tube wherein the projectionsare disposed in a helical manner, as desired.

In any event, it can be seen that the tube 26 provides a smooth surfaceover the convolutions 22 and provides a consistent base for receivingthe reinforcement 27 thereon. The material of the tube 26 can be chosenso that it will adhere to the outer surface of the apexes 29 of theinner tube 21 so that the layer 26 does not fill the recesses 23 of theinner tube 21 and is applied in a manner to just cover the convolutions22 in substantially the straight-line manner illustrated in FIG. 3because, as previously stated, if the layer 26 were to fill the recesses23, not only would the tube 26 then reduce the flexibility of the innerhose 21, but also the same would then allow the reinforcement 27 toenter those recesses 23 to further reduce the flexibility of the innerhose 21.

After the outer tube 26 has been applied in place in the mannerpreviously set forth, the reinforcement sleeve 27 of either a braidedtextile material or a metal wire material that is wound in alternatingdirections is disposed over the tube 26 and the amount of reinforcementprovided is dependent upon the working pressure requirements of the hoseconstruction 20.

For example, the reinforcement sleeve 27 is illustrated as a braidedmaterial in FIG. 4 and thereby comprising a seamless sleeve of suchmaterial whereas the reinforcement 27A of FIG. 7 is illustrated as twolayers of helically wound wire material disposed in opposite directionson the tube 26A.

In any event, it can readily be seen in FIG. 4 that the reinforcementsleeve 27 does not enter the recesses 23 of the inner hose 21 to anysubstantial amount because the tube 26 prevents the same from beingforced into the recesses 23 as the reinforcement sleeve 27 is beingapplied to the desired thickness on the inner tube 21.

Thereafter, the outer layer 28 of any suitable polymeric material isapplied over the reinforcement 27 such as by being extruded as acontinuous tube thereof by conventional extruding apparatus to completethe hose construction 20 or by being applied in a helically wound formthereof from a strip 33 of such outer material in the manner illustratedin FIG. 8 to complete the hose construction 20A.

In any event, the outer layer 28 provides protection for thereinforcement 27 and can readily bond to the inner tube 26 by exudingthrough the reinforcement 27 in a manner well known in the art and asillustrated in FIG. 5 so as to hold all of the layers of the hoseconstruction 20 in a bonded condition thereof, if desired.

The material of the outer layer 28 not only protects the reinforcement27 from physical or chemical damage, but also the cover layer 28 ischosen with consideration to the environment and bondability to theother layers of the hose construction 20. In addition, the material 28can be chosen so as to tend to prevent the liquid flowing through thehose construction 20 from permeating through the hose construction 20 tothe exterior thereof.

As previously stated, the materials of the hose construction 20 of thisinvention can be any suitable materials that function in the mannerpreviously set forth.

Therefore, the following example of one working embodiment of the hoseconstruction 20 of this invention is not to be a limitation on thisinvention and is merely being given as one working example thereof.

In the one working embodiment of this invention, the inner hose isformed in the manner of FIG. 9 with the inner layer 21' comprising athermoplastic material sold by DuPont as Zytel ST811HS and with theouter layer 21" thereof comprising a thermoplastic material sold by theB. F. Goodrich Company as ESTANE 5710F1. Such material is blow molded toform the hose 21B with an inside diameter of approximately 1.500 of aninch and with the distance between the apexes 29B of the projections 22Bbeing approximately 0.246 of an inch. The thickness of the innerportions 34 of the hose 21B is approximately 0.045 of an inch while thesidewalls 35 between the portion 34 and the apexes 29B are actuallydisposed at an angle relative to each other rather than being parallelto each other as illustrated in FIGS. 2 and 3, such angle of eachsidewall 35 being approximately 10° to a true transverse line passingthrough the inner hose 21B.

The tube 26 in such working embodiment of the hose construction 20 ofthis invention also comprises the thermoplastic material ESTANE 5710F1and is approximately 0.040 of an inch thick while the reinforcement 27comprises a polyester yarn formed on a thirty-six carrier braidingmachine with two ends per carrier and the outer layer 28 comprises thethermoplastic material ESTANE 5710F1 and is approximately 0.060 of aninch thick.

In this manner, the thermoplastic material of the cover 28 readily bondsto the tube 26 and the thermoplastic material of the tube 26 readilybonds to the outer layer 21" of the inner tube 21B.

Therefore, it can be seen that the resulting hose construction 20 or 20Aof this invention is readily adapted to be utilized for conveying anydesired fluid therethrough, such as a volatile liquid, and will permitthe hose construction 20 or 20A to be disposed in a bent configurationfor such purpose as desired.

Thus, this invention provides a new flexible hose construction and a newmethod of making such a flexible hose construction.

While the forms and methods of this invention now preferred have beenillustrated and described as required by the Patent Statute, it is to beunderstood that other forms and method steps can be utilized and stillfall within the scope of the appended claims wherein each claim setsforth what is believed to be known in each claim prior to this inventionin the portion of each claim that is disposed before the terms "theimprovement" and sets forth what is believed to be new in each claimaccording to this invention in the portion of each claim that isdisposed after the terms "the improvement" whereby it is believed thateach claim sets forth a novel, useful and unobvious invention within thepurview of the Patent Statute.

What is claimed is:
 1. In a method of making a flexible hoseconstruction comprising the steps of forming an inner corrugated hose ofpolymeric material to have a plurality of outwardly convex projectionswith recesses therebetween, disposing an outer sleeve of reinforcingmaterial in telescoping relation on said inner hose, and disposing anouter sleeve of polymeric material in telescoping relation on saidsleeve of reinforcing material, the improvement comprising the steps ofdisposing a tube of polymeric material between said sleeve ofreinforcing material and said inner hose by extruding said tube ontosaid inner hose before disposing said sleeve of reinforcing materialthereon, the step of extruding causing said tube to have substantiallyconstant inner and outer diameters whereby said tube extends in agenerally straight-line manner from projection to projection of saidinner hose so as to prevent said sleeve of reinforcing material fromthereafter entering into said recesses of said inner hose an amount thatwould tend to substantially reduce the flexibility characteristics ofsaid inner hose, forming said inner hose with an outer layer of onethermoplastic material and an inner layer of a different thermoplasticmaterial, forming said tube of polymeric material from the samethermoplastic material that forms said outer layer of said inner hose,forming said outer sleeve of polymeric material of the samethermoplastic material that forms said tube of polymeric material, thestep of extruding causing said tube of polymeric material to be bondedto said projections of said inner hose, and bonding said sleeve ofpolymeric material to said tube of polymeric material through saidsleeve of reinforcing material by extruding said sleeve of polymericmaterial onto said sleeve of reinforcing material whereby said tube ofpolymeric material holds said sleeves and said hose together.
 2. Amethod of making a flexible hose construction as set forth in claim 1and including the step of forming said projections to be annular and bedisposed substantially transverse to the longitudinal axis of said hoseconstruction.
 3. A method of making a flexible hose construction as setforth in claim 1 and including the step of forming said projections ofsaid inner hose to extend in a helical path about the longitudinal axisof said hose construction.